Method for performing orthodontic ligation of the bands and the archwire applied to a series of teeth, and an orthodontic ligation brace and a preshaped ligation wire piece for use in said method

ABSTRACT

Orthodontic ligating operation is conducted with a greatly increased efficiency and economy by the use of a preshaped ligation wire piece having a forward loop section, an adjacent intermediate widened section and a rodlike twisted end portion extending from said intermediate section, and by having said end portion held firmly between the grasping arms of a chuck means contained in a pencillike orthodontic ligation brace and adapted to be closed by a chuck closing and opening means provided in said brace, then hooking the brackets of the selected band and an archwire which have been already applied to a tooth, thereafter twisting up the wire piece by turning said brace until said brackets and archwire are firmly fixed together by said loop, and then opening said arms of the chuck to release the end portion of the fixed wire piece therefrom.

United States Patent [56] References Cited UNITED STATES PATENTS [72] Inventor Takeshi Matsumoto 27-5, Hakusan lchorne Bunkyo-ku, Tokyo, 113. Japan 66 d 66 e l/ t 22 c 33 U n o c .5 "u n n" .m n t a "u f "u n W mm m 0 Mm h 2. aw .m n" I mmm m. eh i en m .m Mm: m M a 60 0 W1 m r o .l mu m a 00 0 wk A ,3 D R 72 am T 003 m S H" B 12 PA A 911 79 91 a 2 0 m sl m msm s m wv, 8MANJ4 o. d N mw .l m n Wet.w har. AFB-D- IIII with a greatly increased efficiency and economy by the use of a preshaped ligation wire piece having a forward loop section,

an adjacent intermediate widened section and a rodlike twisted end portion extending from said intermediate section, and by having said end portion held firmly between the grasping arms of a chuck means contained in a pencillike orthodontic ligation brace and adapted to be closed by a chuck closing and opening means provided in said brace, then hooking the brackets of the selected band and an archwire which have been already applied to a tooth, thereafter twisting up the wire piece by turning said brace until said brackets and archwire are firmly fixed together by said loop, and then opening said arms of the chuck to release the end portion of the fixed wire piece therefrom.

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SHEET 2 [IF 2 INVENTOR. T ah: ma-luumolo (2. M Daub; Gushmm A'Iformys BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is concerned with a method for performing orthodontic ligation and also with an orthodontic ligation brace and a preshaped ligation wire piece which are used for putting said method into practice.

2. Description of the Prior Art Known procedure of orthodontic ligation comprises applying a plurality of metal bands having brackets onto a series of teeth, one for each tooth, passing an archwire through said brackets and then fixing said archwire and said brackets together with a ligation wire.

In the past, the ligation or the tying up of the archwire and the bracket was conducted by the use of a vice and utilizing a considerable length of wire. In operation, the foremost end portions of the arms of a vice were inserted into the mouth of the patient, and this often caused a sense of terror in those patients who received orthodontic ligation of teeth for the correction of irregular row of the teeth. Besides, a difficulty was encountered in performing the ligation or tying up of especially those brackets and archwire which were applied to the back teeth located in the posterior section in the mouth. Moreover, orthodontic ligation of the prior art which was conducted by the use of a vice required a considerable length of ligation wire which, in operation, was folded in the middle portion thereof to form a loop for hooking the brackets of a band, and after the ligation process was completed, the surplus portions of the ligation wire which extended in two free ends and which still was of a considerable length were cut off from the twisted section of the ligation wire, and they were discarded. This was quite against economy. In addition, the twisting of a length of looped wire by the use of a vice was not an easy thing for the operator to perform, especially where the twisting was to be conducted on a tooth located in the posterior section of the mouth.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to eliminate the drawbacks, difficulty and inconveniences which were encountered in the past in performing an orthodontic ligation of the brackets of a band and the archwire which were applied to one of a series of teeth and especially where a vice was used in doing this ligation, and to provide an improved method for accomplishing an orthodontic ligation of the type described without such difficulty or inconveniences and without causing a sense of terror in the patient who receives such an orthodontic operation, and also to provide an improved orthodontic brace and a ligation wire piece for use in such operation.

Another object of the present invention is to provide an improved method for performing an orthodontic ligation of the type described which permits the operator to accomplish this ligation with a great deal of easiness and surety and to also provide an improved orthodontic brace and a preshaped wire piece for use in attaining this object.

Still another object of the present invention is to provide an improved method for performing an orthodontic ligation of the type described which enables the operator to accomplish this ligation for a length of time as small as one-third or less than that of the time required in the past for doing the same thing by relying on the technique and the tool of the prior art, and to also provide an improved orthodontic ligation brace and a preshaped wire piece for use in attaining this object.

Yet another object of the present invention is to provide a method for performing an orthodontic ligation of the type described by the use of a small piece of preshaped wire, which saves the loss of a considerable length of wire which was inevitable in the past and which, accordingly, affords a much greater economy as compared with the prior art of this kind and to also provide an orthodontic ligation brace and a preshaped ligation wire piece for use in attaining this object.

Other objects and attendant advantages of the present invention will become apparent by reading the following detailed description in conjunction with the accompanying drawing which is given only by way of example and not by way of limitation.

BRIEF DESCRIPTION OF THE DRAWING FIGS. 1 through 4 show one example of the orthodontic ligation brace of the present invention, and more specifically,

FIG. 1 is a more or less diagrammatic longitudinal sectional view of the orthodontic ligation brace in the state in which the bifurcate arms of the chuck means are opened apart;

FIG. 2 is a more or less diagrammatic longitudinal sectional view of the orthodontic ligation brace of the type shown in FIG. 1 which is in the state in which the bifurcate arms of the chuck means are closed;

FIG. 3 is a more or less diagrammatic cross-sectional view taken along the line Ill-III in FIG. 1;

FIG. 4 is a more or less diagrammatic cross-sectional view taken along the line IV-IV in FIG. 1;

FIGS. 5 and 6 represent one example of the preshaped looped ligation wire piece for use with the orthodontic ligation brace of the present invention, in which:

FIG. 5 is a somewhat diagrammatic plan view of the wire piece;

FIG. 6 is a somewhat diagrammatic side elevation of the same;

FIG. 7 is a more or less diagrammatic explanatory representation showing the manner in which a series of teeth are subjected to orthodontic ligation operation;

FIG. 8 is a more or less diagrammatic explanatory representation, in an enlarged scale, showing the manner in which the method for orthodontic ligation of the present invention is applied to a series of teeth;

FIG. 9 is a more or less diagrammatic front elevation, in an enlarged scale, of a tooth to which orthodontic ligation is applied; and

FIG. 10 is a more or less diagrammatic plan view of the same.

DESCRIPTION OF THE PREFERRED EMBODIMENT The method of the present invention and the orthodontic ligation brace and the preshaped ligation wire piece for use in materializing said method will hereunder be described in further detail by referring to the accompanying drawing which illustrates, by way of example and not by way of limitation of the invention, an embodiment of the orthodontic ligation brace and the preshaped ligation wire piece of the present invention for use in practicing said method.

The orthodontic ligation brace of the present invention is so designed as to be operative in such a way that the rodlike twisted end portion of a preshaped ligation wire piece A is first firmly grasped between the forward end portions of the bifurcate arms of the chuck means contained in the ligation brace and then the bracket section C of the band B is hooked, together with an archwire D, by the loop of said wire piece, and then the brace is turned to tightly tie up and fix these two members together by said wire piece as the brace is turned, in the manner as shown in FIGS. 7 through 10. The letter E represents the teeth which are to be straightened of their irregular set.

The preshaped ligation wire piece A which is used with the ligation brace of the present invention is prepared, as shown in FIGS. 5 and 6, by bending a predetermined length of wire to form a forward narrow U-shaped section 1 and then by forming an adjacent intermediate section 2 which consists of two extensions of the wire which are spaced slightly wider than the U-shape section and than the width of the bracket section C, and then by twisting the remaining end portions of said extensions together into a rodlike twisted end portion 3. Said for ward narrow U-shape section of the wire piece may be inclined relative to the adjacent intermediate section, as required, in the form as will be best seen in FIG. 6, but this inclination of the U-shape section is not an indispensable requirement of the invention.

The ligation brace of the present invention is ofa pencillike shape and comprises an elongated hollow cylindrical body 4 and a forward conical-headed cylindrical member 6 which is connected to said cylindrical body 4 by means of an intermediate cylindrical member 5.

Said forward conical-headed cylindrical member 6 is provided, in the foremost end portion thereof, with a narrow through-hole 7 through which the rodlike twisted end portion 3 of said ligation wire piece A is inserted. This narrow through-hole 7 opens into the space defined by the tapered inner wall face 8 of the conical-headed portion of the member 6. in said apace inside the conical-headed cylindrical member 6 is housed a chuck means 9 which is arranged so as to be axially slidable therein. This chuck means 9 is provided with a deep notch 10 to thereby form bifurcate foremost free end portions which serve as the grasping sections. The foremost free end portions of the bifurcate arms are so formed as to have tapered external peripheral faces 11 to insure the following operation such that, as said chuck means 9 is advanced forwardly, said conical-shaped head portions of the bifurcate arms will become engaged and nipped progressively by the surrounding tapered inner wall face 8 of the aforesaid conicalheaded cylindrical member 6 to thereby progressively tighten the bifurcate arms of the grasping section 12 which are formed in the foremost end portions of the notch 10 and that, as the chuck means 9 is caused to retreat axially in the space in said cylindrical member 6, then closed bifurcate arms of the grasping sections l2 will diverge or open progressively by their own spring action to restore their initial positions. The inner faces of said grasping sections 12 of the chuck means 9, in this example, are indented or serrated to insure that the aforesaid rodlike twisted end portion 3 of the ligation wire piece is grasped and held positively and firmly by these bifurcate arms of the grasping sections 112 when the conical-shaped head portions of the chuck means 9 are tightened in the manner as described above.

Reference numeral 13 represents a guide ring which is fixed in an annular recess formed in the inner circumferential wall face of the foremost end portion of the conical-headed cylindrical member 6 and which is adapted for guiding the advancemerit and the retreat movement of the chuck means 9 and it also serves as the stopper for a spring 18 so as to support the foremost end thereof and to inhibit the forward travel of said spring 18 beyond the rear end of the stopper. Numeral R4 represents a threaded rod which protrudes axially rearwardly from the rear end of said chuck means 9. Said threaded rod 141 is screwed into a lock nut 16 and therefrom further into a rear end fitting l5 which is located at the rear end of said lock nut 16. Said rear end fitting is inserted in a guide ring 17 which, in turn, is fixed to the inner wall face of the foremost end portion of the cylindrical body 4. The axial sliding movement of said chuck means 9 is guided by this guide ring 17 and by the aforesaid guide ring 13 which, in turn, is fixed to the inner wall face of said conical-headed cylindrical member 6. Numeral 18 represents a coil spring which is located between said guide ring 13 and said lock nut 16. Said coil spring 18 is of a length such that it will become compressed when the cylindrical body 4 is coupled, by said intermediate cylindrical member 5, to the conical-headed cylindrical member 6, said coupling being effected by screwing the male thread which is formed on the outer surface of one free end of each of said cylindrical body and said conical-headed cylindrical member 6 into the female thread which is formed on the inner wall face of each of the opposite end portions of said intermediate cylindrical member 5.

A chuck supporting and operating member 20 has one end which is pivotably supported by a pin 19 in an elongated recess which is formed on the foremost end side of the cylindrical body 4, and more specifically in the portion of said cylindrical body 4 adjacent to said intermediate cylindrical member 5. This chuck supporting and operating member 20 is generally of an elongated shape and has a tapered foremost end face to form an acute-angled edge portion and an obtuseangled edge portion as will be best seen in FIGS. 1 and 2. The acute-angled end edge portion of said chuck supporting and operating member 20 is positioned within said recess of the cylindrical body Al, whereas the obtuse-angled portion of this member 20 adjacent to said acute-angled end edge portion is pivotably supported inside said cylindrical body 4 by a pin 19 which is provided on the inner wall of said cylindrical body 4.

Because of the arrangement described above of the ligation brace, it will be understood easily that, when there is applied no external force to the chuck supporting and operating member 20, the chuck means 9 is urged to move backwardly by the restoring force of the spring 18 so that, under this condition, the bifurcate arms of the grasping sections 12 of the chuck 9 are retained in their open state and also that, along with this, the rear end of the chuck means 9 and accordingly the rear end of the rear end fitting 15 will bear against the foremost end face 21 of the chuck supporting and operating member 20, with the result that the rear end portion of said chuck supporting and operating member 20 is caused to thrust itself outwardly of the cylindrical body 4. When, on the other hand, the chuck supporting and operating member 20 is pushed, from this state, into the recess of the cylindrical body 4 by the application of an external force exerted by, for example, a finger of the operator, the rear end fitting l5 and accordingly the chuck means 9 will be urged to advance forwardly by the apex of the acute-angled portion of the chuck supporting and operating member 20, against the force of the spring 13, with the result that the bifurcate arms of the grasping sections 12 of the chuck means 9 will be closed together by the cooperation of the tapered inner wall face 8 and the guide ring 13. During this operation, the chuck supporting and operating member 20 functions as a lever which is adapted to make pivotal movement about the pin 19 which, in turn, serves as the fulcrum. Therefore, when it is intended to push the rear end outwardly thrusting portion of the chuck supporting and operating member 20 into the recess of the cylindrical body 4, there is required only a very small amount of force to accomplish this push-in operation.

Numerals 22 and 23 represent stepped portions which are formed on the rear end face of the chuck supporting and operating member 20. These stepped portions serve to retain the chuck means 9 in its closed state by the cooperation between one of said stepped portions and a latching member 24 which is mounted within the cylindrical body 4, and also serve to release the chuck means 9 of its closed state by the cooperation of the other of said stepped portions and said latching member 24. This latching member 24 is provided, at one edge of one end thereof, with a latching projection 25 and, at the other edge of said one end thereof, with a lug 26 or an integral portion. Said latching projection 25 is adapted to be brought into engagement with said stepped portions 22 and 23. Said lug 26, on the other hand, is coupled, by a pin 28 inserted through a longitudinal slot 27 which is formed in the wall of the cylindrical body 4 on the side constituting the base of said recess, to a button 29 which is provided on the external side of the cylindrical body 41. This latching member 24 is normally urged axially toward the foremost end of the cylindrical body 4i by means of a coil spring 30. Therefore, when the chuck means 9 is in the retreated position where the bifurcate arms of the grasping sections 12 of the chuck means 9 are opened apart and where the rear end portion of the chuck sup porting and operating member 20 is in the position of thrusting outwardly of the cylindrical body 4, the stepped portion 22 is retained in its state of being engaged by the latching projection 25. When, however, the chuck supporting and operating member is pushed, from its outwardly thrusting position, back into the recess of the cylindrical body 4 to the position in which its stepped portion 23 is about to be brought into engagement with the latching projection 25, the latching member 24 will be caused to advance forwardly by the action of the spring 30, with the result that the latching projection 25 will be automatically brought into engagement with the stepped portion 23 of the member 20. After this engagement is established, the operator may relieve the chuck supporting and operating member 20 of the pressure which has been applied thereto by, for example, one of the fingers of the operator, since the latching projection 25 will be positively brought into and retained in the state in which it is engaged by the stepped portion 23, or in other words, the bifurcate arms of the grasping sections 12 will be retained in the state in which they are closed. When, from this state of the ligation brace, the button 29 is pulled in the direction of the arrow given in FIG. 2, the latching projection 25 will become be caused to retreat rearwardly by the restoring force of the spring 18 so that the bifurcate arms of the grasping sections 12 will accordingly be opened apart while, on the other hand, the rear end portion ofthe chuck supporting and operating member 20 will thrust outwardly of the cylindrical body 4 to return to its position shown in FIG. 1. Numeral 31 represents a stopper fitting which is screwed into the threaded inner face of the rear end portion of the cylindrical body 4 and is adapted to limit the rearward movement of the spring 30.

The orthodontic ligation brace of the present invention is of the foregoing structure so that it is only necessary for the operator to insert the rodlike twisted end portion 3 of the ligation wire piece A through the narrow through-hole 7 provided in the foremost end portion of the brace while the bifurcate arms of the grasping sections 12 of the chuck means 9 are in the state of being opened apart and then to lightly push the rear end portion of the chuck supporting and operating member 20 into the recess of the cylindrical body 4 by. for example, one of the fingers of the operator, in order to positively firmly grasp said end portion 3 of the wire piece A between the grasping sections 12 of the chuck means 9. Thereafter, the intermediate section 2 of the wire piece which consists of widely spaced two extensions of the wire are applied onto the selected band B and also the archwire D in such a manner as to surround the bracket section C which is provided on said band B, and then the ligation brace and accordingly the wire piece which is held by the latter are pulled together in the direction shown by the arrow in FIG. 8. whereupon, the brackets C will be brought into engagement with the narrow loop 1 of the wire piece. At this moment, the ligation brace is turned by, for example, the fingers of the operator to such an extent as will sufficiently tighten the engagement of this loop section 1 of the ligation wire piece A with said brackets C and with said archwire D, and thus, they are fixed together.

It is to be noted that, by the employment of the preshaped ligation wire piece, it is possible to save the loss of a considerable length of ligation wire which was inevitably wasted in the past especially where the ligation was performed by relying on the orthodontic ligation technique of the prior art in which a vice was employed. Moreover, the use of the ligation brace of the present invention almost complete relieves the patient of the sense of terror which was caused priorly by the use of a conventional vice. in addition, the brace and the wire piece of the present invention save much of the time which was required before in doing the orthodontic ligation of teeth in the prior art.

Description has been directed to an example of the ligation brace which, in performing the tightening and fixing of the brackets and the archwire with a ligation wire piece, was turned manually by, for example, the fingers of the operator. It should be understood, however, that a micromotor which is equipped with a speed-reducing mechanism may be coupled to the rear end of the ligation brace of the present invention so that the brace may be turned automatically by driving said micromotor. Many other modifications and changes of the present invention maybe made, as desired, by those skilled in the art without departing from the spirit of the invention.

I claim:

1. Apparatus for performing an orthodontic ligation operation with a preformed wire piece comprising, in combination,

a tubular, hollow, cylindrical member having a tapered end portion, a narrow opening through said tapered end portion, a chuck element having bifurcated arms disposed within said member, said bifurcated arms having at their ends wire grasping sections movable between open and closed positions and located adjacent said opening, said chuck element being movable longitudinally in said member between a retracted, first position and a second position with respect to said opening, said chuck element having at its end, remote from said opening, support means for cooperation with the interior wall of said opening, said cylindrical member having spring means engaging said support means of said chuck element for constantly urging said chuck element into said first position wherein said wire-grasping sections will be retracted from said opening and will be in said open position, said cylindrical member having movable latch means engaging said support means of said chuck element whereby movement of said latch means will effect movement of said chuck element from said retracted first position to said second position to effect closing of said wiregrasping sections; and

said wire piece having a loop-shaped portion and a rodlike twisted end portion extending from said loop portion, said twisted end portion having a longitudinal dimension such that, upon insertion of said twisted end portion into said opening of said cylindrical member, said wire grasping sections will firmly grasp said twisted end portion when said chuck element is moved to said second position.

2. The apparatus as claimed in claim 1 wherein said cylindrical member is provided with releasable detent means for engaging said movable latch means.

3. The apparatus as claimed in claim 2 wherein said latch means comprises a lever pivotally mounted on said member for movement between a first and second position corresponding to said first and second positions of said chuck element, said lever having a tapered end face for engaging said support means of said chuck element and said cylindrical member is provided with a slot through which said lever protrudes when said lever is in said first position.

4. The apparatus as claimed in claim 3 wherein said cylindrical member is provided with a releasable detent member and said lever is provided at its end remote from said pivot mount with stepped recesses for engaging said detent member, said detent member engaging one of said stepped recesses when said lever is in said second position whereby said lever is releasablyretained in one of said two positions.

5. The apparatus as claim 4 wherein said cylindrical member carries spring means for constantly urging said detent member into engagement with one or the other of said stepped recesses of said lever and manually engageable means are provided on the exterior of said cylindrical member for disengaging said detent member from said other of said stepped recesses when said lever is in said second position.

6. The apparatus as claimed in claim 1 wherein said bifurcated arms of said chuck element are formed from resilient material and formed at their ends with exterior tapered surfaces adjacent said wire-grasping sections, and the interior surface of said cylindrical member adjacent said opening is formed with a tapered conical surface at the apex of which is located said opening, whereby, upon movement of said chuck element from said first retracted position to said second position, said tapered surfaces of said bifurcated arms will engage said tapered conical surface of said cylindrical member to close said wire-grasping sections and when said chuck element moves from said second position to said first position, said wire-grasping sections will open.

to surround the bracket section provided on a band applied to a tooth, and a rodlike twisted end portion extending from said intermediate section and having a twisted free end. 

1. Apparatus for performing an orthodontic ligation operation with a preformed wire piece comprising, in combination, a tubular, hollow, cylindrical member having a tapered end portion, a narrow opening through said tapered end portion, a chuck element having bifurcated arms disposed within said member, said bifurcated arms having at their ends wire grasping sections movable between open and closed positions and located adjacent said opening, said chuck element being movable longitudinally in said member between a retracted, first position and a second position with respect to said opening, said chuck element having at its end, remote from said opening, support means for cooperation with the interior wall of said opening, said cylindrical member having spring means engaging said support means of said chuck element for constantly urging said chuck element into said first position wherein said wiregrasping sections will be retracted from said opening and will be in said open position, said cylindrical member having movable latch means engaging said support means of said chuck element whereby movement of said latch means will effect movement of said chuck element from said retracted first position to said second position to effect closing of said wire-grasping sections; and said wire piece having a loop-shaped portion and a rodlike twisted end portion extending from said loop portion, said twisted end portion having a longitudinal dimension such that, upon insertion of said twisted end portion into said opening of said cylindrical member, said wire grasping sections will firmly grasp said twisted end portion when said chuck element is moved to said second position.
 2. The apparatus as claimed in claim 1 wherein said cylindrical member is provided with releasable detent means for engaging said movable latch means.
 3. The apparatus as claimed in claim 2 wheRein said latch means comprises a lever pivotally mounted on said member for movement between a first and second position corresponding to said first and second positions of said chuck element, said lever having a tapered end face for engaging said support means of said chuck element and said cylindrical member is provided with a slot through which said lever protrudes when said lever is in said first position.
 4. The apparatus as claimed in claim 3 wherein said cylindrical member is provided with a releasable detent member and said lever is provided at its end remote from said pivot mount with stepped recesses for engaging said detent member, said detent member engaging one of said stepped recesses when said lever is in said second position whereby said lever is releasably retained in one of said two positions.
 5. The apparatus as claim 4 wherein said cylindrical member carries spring means for constantly urging said detent member into engagement with one or the other of said stepped recesses of said lever and manually engageable means are provided on the exterior of said cylindrical member for disengaging said detent member from said other of said stepped recesses when said lever is in said second position.
 6. The apparatus as claimed in claim 1 wherein said bifurcated arms of said chuck element are formed from resilient material and formed at their ends with exterior tapered surfaces adjacent said wire-grasping sections, and the interior surface of said cylindrical member adjacent said opening is formed with a tapered conical surface at the apex of which is located said opening, whereby, upon movement of said chuck element from said first retracted position to said second position, said tapered surfaces of said bifurcated arms will engage said tapered conical surface of said cylindrical member to close said wire-grasping sections and when said chuck element moves from said second position to said first position, said wire-grasping sections will open.
 7. An orthodontic ligation wire piece according to claim 1, wherein said wire piece is of the shape consisting of a forward narrow U-shape section, an adjacent intermediate section having two extensions of the loop which are spaced wide enough to surround the bracket section provided on a band applied to a tooth, and a rodlike twisted end portion extending from said intermediate section and having a twisted free end. 